CVE-2021-26324

Guest-memory corruption via undisclosed SEV-ES TMR bug

Published May 10, 2022 · Updated Sep 16, 2024

Memory-integrity failure in AMD 3rd Gen EPYC before MilanPI-SP3_1.0.0.4 allows local users to corrupt SNP-active VM memory. AMD has not disclosed the specific SEV-ES TMR operation that mishandles memory or the triggering input. Low-privilege local access and an SNP-active virtual machine are required; the bounded consequence is loss of guest-memory integrity.

CVSS severity7.8
High
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory-integrity failure in AMD 3rd Gen EPYC before MilanPI-SP3_1.0.0.4 allows local users to corrupt SNP-active VM memory. AMD has not disclosed the specific SEV-ES TMR operation that mishandles memory or the triggering input. Low-privilege local access and an SNP-active virtual machine are required; the bounded consequence is loss of guest-memory integrity.

The record

CVE
CVE-2021-26324
Published
May 10, 2022
Updated
Sep 16, 2024
Vendor
Advanced Micro Devices, Inc.
Product
3rd Gen AMD EPYC Processors
Classifications
T1565
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 10, 2022CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <MilanPI-SP3_1.0.0.4

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Advanced Micro Devices, Inc. · 3rd Gen AMD EPYC Processorsversion=unspecified <MilanPI-SP3_1.0.0.4

Published CVSS scores

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.2NIST NVDAV:L/AC:L/Au:N/C:C/I:C/A:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1565Data Manipulation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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